Iran’s leadership warned on Sunday that a U.S. attack would trigger a regional conflict, escalating tensions between Tehran and Washington amid mounting disputes over Iran’s nuclear programme and domestic unrest.

The warning came as the United States reinforced its naval presence in the Middle East after President Donald Trump repeatedly threatened military action if Iran failed to agree to a new nuclear deal or continued cracking down on protesters.

In a parallel development, armies from several European Union countries designated Iranian-linked groups as “terrorist organisations,” in response to a similar move by the bloc against Iran’s Revolutionary Guards, further straining ties between Tehran and Western capitals.

Despite the standoff between Iran’s clerical leadership and the Trump administration, both sides have signalled openness to resuming talks, while regional powers such as Turkey have sought to ease tensions and prevent a broader confrontation.